So now there's a Grand Theft Auto IV mod that lets you play as an Elephant instead of Niko. The elephant looks to have access to at least the ground and water vehicles and can use them with extreme prejudice. This video needs to be seen. The motorised carnage starts at 2:40.
The mod is the work of one Indirivacua, who has also created a giraffe mod, as well a whole host of other characters including Slanderman, the Teletubbies and er, Sean Paul. Check out his page at GTAGaming.com to get hold of them. He has given the world a base-jumping elephant, and this he deserves your respect.